Golf shoe spike

ABSTRACT

A golf shoe spike fabricated from a soft thermoplastic rubber and including a one-piece body member with a planar base having a proximal surface and a distal surface, and a self-threading stud of a length shorter than the threaded spike socket into which it is inserted at installation. The spike includes an outer planar face which may further included a plurality of traction segments integral with the distal surface of the planar base and extending radially outward from the center of the planar base, each of said segments separated from adjoining segments by a notch. The spike cups when tightly screwed into a threaded spike socket, thus forming a rim on the outer circumference of the outer planar face.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/499,271, filed Feb. 7, 2000.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to a shoe cleat, and more particularly to a flat, single-piece, soft plastic golf shoe spike.

[0004] 2. Discussion of Related Art

[0005] Until the late 1980s and early 1990s no one seriously questioned whether conventional metal golf spikes provided the most desirable performance characteristics for golf shoe spikes. The gripping and traction characteristics were, and are, immediately evident to the wearer. In addition, metal spikes were long supposed to provide aeration to putting greens as golfers walked over the greens. However, the United States Golf Association conducted studies that showed this benefit to be more hypothetical than real and that metal spikes actually compacted the soil on putting surfaces. These studies also established that the punctures and tears created on putting greens by metal spikes make the greens vulnerable to encroachment by non-indigenous or otherwise undesirable species of turf grass and other gramineous plants. Such damage to putting surfaces has a significant economic impact on greens maintenance costs. Later still, studies showed that metal spikes have a deleterious effect on walking mechanics, particularly when walking on impenetrable surfaces, and may contribute to joint stress.

[0006] Consequently, an incentive quickly arose to develop alternatives to conventional metal golf shoe spikes, some attempts being much more successful than others. It was hoped and believed that practicable alternatives to metal spikes could be developed to provide the traction and gripping desired by golfers while decreasing green surface damage and reducing joint stress. By the mid-1990s a high percentage of golf courses had imposed a ban on the use of metal spikes. Thus began the “alternative spike” era, which continues to this day. Largely due to the policy-driven market for alternative spikes, shoe manufacturers and independent inventors alike have been working feverishly to develop a spike with the proper balance of several characteristics: traction under all normal playing conditions; comfort; durability and even wear; safety; resistance to the accumulation of dirt and debris; compatibility with proper walking mechanics; and minimal impact on various grass surfaces, outdoor finished surfaces, paths, and floor coverings. The result is an increasingly crowded field of shoe spike designs, from the prosaic to the genuinely exotic. A few representative examples are set out below.

[0007] U.S. Pat. No. 5,367,793 to Deacon et al. discloses a replaceable golf shoe spike having a plastic main body with a metal threaded stud formed on the upper surface of a concavo-convex flange. The bottom surface of the flange has a plurality of triangular traction ribs protruding downwardly and radiating from the center of the flange to form an uneven surface topography.

[0008] U.S. Pat. No. 5,727,340 to Suk teaches a golf shoe spike that purports not to produce spike marks in a putting green. The spike is fabricated of plastic and is shaped with a non-circular peripheral edge on its main body for improved engagement with a specially designed spike wrench. The main body is generally flat but includes a plurality of points or mini-spikes protruding outwardly for engagement with the ground.

[0009] U.S. Pat. No. 5,794,367 to Carroll discloses a shoe spike having a dome-shaped main body, a planar inner face, an integrally molded thread projecting from the inner face, and a plurality of pyramid-shaped traction teeth projecting from the perimeter of the dome-shaped main body.

[0010] U.S. Pat. No. 5,901,472 to Adam teaches a shoe system for spikes comprising a shoe with a non-metal screw boss and a cleat. The cleat, or spike, of the system has a disc-shaped body with a downwardly projecting, generally circular pattern of ridges forming a surface topography on the cleat.

[0011] Finally, U.S. Pat. No. 5,964,048 to Shieh discloses a golf shoe spike having a disc-shaped main body with a plurality of stubs extending downwardly from the underside of the main body at its periphery.

[0012] While the foregoing inventions and their non-patented siblings offer some advantages to the user, none provide the traction of conventional metal spikes while simultaneously providing the other desirable characteristics of golf spikes. Despite claims to the contrary, all of the foregoing designs include surface topography (namely downwardly projecting spikes) that leaves a considerable imprint in putting greens, a nightmare to anyone standing over a meaningful putt. These designs also penetrate putting green surfaces leaving them vulnerable to infestation by noxious weeds. Furthermore, the spikes are typically fabricated from hard plastics and plastic/metal combinations that break easily, wear unevenly, slide on slippery surfaces, and affect walking mechanics; on slick or hard surfaces the wearer usually limits or eliminates proper ankle roll and any idiosyncratic pronation/supination to reduce both shock to the foot and ankle and to decrease the chances of slipping. The departure from the natural gait pattern fatigues the wearer and causes considerable discomfort. Finally, the known designs tend to accumulate mud and debris that reduce traction and increase the chance of losing one's base when swinging a golf club or one's footing when walking on even nominally slippery or sloped surfaces.

[0013] It would be desirable, therefore, to provide a golf shoe spike that strikes an optimal balance between traction and other wearing characteristics.

SUMMARY OF THE INVENTION

[0014] The golf shoe spike of the present invention provides performance characteristics superior to all known spike designs. The spike comprises a flexible, soft plastic, one-piece primary body member with a planar base having a proximal (sole-side) surface and a distal (ground-side) surface. In a first preferred embodiment, an outer face which is substantially planar and substantially circular is formed by a plurality of traction digits or segments integral with the ground-side surface of the planar base and extending radially outward from the center of the planar base, each of said segments separated by a small notched section. An integral self-threading stud is axially disposed from the sole-side of the planar base and has vertical ribbing to reinforce the stud when inserted into a threaded spike socket or receptacle. The planar outer face includes a substantially rectangular aperture for inserting or removing the spike with a coin or a conventional screwdriver; it also includes two circular apertures for inserting or removing the spike with a conventional spike wrench.

[0015] In a second preferred embodiment, the upper planar surface of the spike is flat and does not include traction digits. However, the self-tapping stud has a length shorter than the depth of the threaded spike socket into which it is to be installed. When tightly screwed into the threaded socket of a shoe, the soft body of the spike permits the central portion of the upper planar surface to be pulled downwardly toward the socket, inducing a kind of puckering or cupping of the spike, and thus forming a raised rim at the outer edge or perimeter of the spike. This feature may be combined with the features of the first preferred embodiment to comprise a third preferred embodiment of the inventive spike.

[0016] In effect, both in design and application, the spike is a flat, low profile cleat that the wearer scarcely notices, even when walking on the most problematic surfaces. Furthermore, the flat design of the spike produces no noticeable imprint in, or nodular penetration of putting greens, a feature certain to please greens superintendents and golfers alike. Other advantages of the design and configuration of the present invention are manifold. Summarily stated, the spike:

[0017] 1. promotes even wear;

[0018] 2. increases comfort due to its shock absorbing characteristics;

[0019] 3. resists the accumulation of mud and debris, thereby maintaining traction in slippery conditions and decreasing the need for cleaning;

[0020] 4. resists picking up and carrying noxious weed and grass seed to the putting green or to other golf courses, or implanting such weed and seed through the surface by penetration;

[0021] 5. improves body weight distribution across the foot, thereby increasing traction and comfort, and decreasing damage to putting green surfaces, especially when pivoting on the foot;

[0022] 6. increases traction on artificial surfaces, such as are found on driving range mats, and also on tile, carpet, cement, asphalt, and the like;

[0023] 7. improves comfort when walking on hard surfaces due to the lack of a hard stud protruding into the shoe sole;

[0024] 8. reduces and virtually eliminates any deleterious effect on walking mechanics;

[0025] 9. facilitates the insertion of the spike into worn or stripped sockets and increases sealing in the socket over time with use;

[0026] 10. eliminates the problem of stripping metal threaded socket that would prevent other spikes from being used;

[0027] 11. increases durability due to the lack of protruding, weight-bearing surface topography that is particularly vulnerable to wear and breakage;

[0028] 12. allows for fabrication from softer materials for further increased comfort and traction on artificial surfaces;

[0029] 13. provides means to conveniently install and remove the spike with a conventional spike wrench, a conventional screwdriver, or a coin;

[0030] 14. improves traction due to the combination of soft material and the unique notches or spaces separating the spike segments, which allow the spike to deform and twist (in contrast the to hard, non-deformable materials and configurations embodied in the prior art);

[0031] 15. reduces noise compared to the hard plastic cleats now available;

[0032] 16. eliminates damage to mowers when lost from a shoe, this due to the soft plastic materials used in fabrication and further due to the lack of a metal shank or stud; and

[0033] 17. produces a gentle propulsive effect to walking forward when walking on hard surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

[0034]FIG. 1 is a perspective view of a first preferred embodiment of the golf shoe spike of the present invention;

[0035]FIG. 2 is a bottom view of the spike of FIG. 1;

[0036]FIG. 3 is a side elevation view of the spike of FIGS. 1 and 2;

[0037]FIG. 4 is a top view of the spike of FIGS. 1-3;

[0038]FIG. 5 is a side perspective view of a second preferred embodiment of the golf spike of the present invention showing its features when not installed in a golf shoe;

[0039]FIG. 6 is a cross-sectional side perspective view in elevation of the spike of FIG. 5 showing the spike's cupping characteristics when installed in a shoe;

[0040]FIG. 7 is a side view in elevation of the spike of FIGS. 5 and 6 shown not installed in a shoe; and

[0041]FIG. 8 is a cross-sectional side view in elevation of both the spike of FIGS. 5-7, and the spike of FIGS. 1-4, again showing the spike's cupping characteristics when installed.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0042] In its first preferred embodiment, the golf shoe spike of the present invention comprises a one-piece primary body member 10 having a distal (ground-side) outer planar surface or face 12 formed by a plurality of traction digits or segments 14. Each of the traction digits are equally spaced by substantially triangular notches 15, and extend radially outward from the geometric center C of the planar base 16 and the outer planar surface 12. The segments are integral with the planar base 16 of the primary body member, which planar base has a distal ground-facing surface 16 a, and a proximal sole-facing surface 16 b, and a substantially circular outer circumference 16 c.

[0043] A stud 18, preferably integral and self-threading, is axially disposed from the sole-facing surface of the planar base and has a proximal end 18 a and a distal end 18 b. Preferably the stud tapers very slightly from its proximal to its distal end and includes vertical ribbing 20 to reinforce the stud when inserted into a threaded spike socket or receptacle. The planar outer surface 12 includes a substantially rectangular aperture, or slot 22, for inserting or removing the spike with a coin or a conventional screwdriver. In addition, the planar outer surface includes at least two circular apertures, or wrench holes 24, positioned within at least two opposing traction segments for inserting or removing the spike with a conventional spike wrench. It is not at all uncommon for wrench holes to become clogged with dirt or debris making removal of the spike with a wrench quite difficult. The alternative slot provides another, more easily cleaned opening for tool-assisted removal of the spike.

[0044] The spike in its entirety is preferably fabricated from a thermoplastic rubber or elastomeric polymer having the desirable wearing and durability characteristics. Extensive testing has shown that a rubber or plastic having a shore A hardness (International Rubber Hardness Degree) of between 80 and 94 is optimal, and a shore A hardness of between 87 and 90 is ideal. This hardness permits the material to deform and twist while in use walking or playing golf and thereby provides both increased traction and increased shock absorption and comfort to the wearer. This is particularly evident in the traction segments, which readily deform and twist into the notches separating the segments to accommodate the forces induced in walking and swinging a club. SANTOPRENE® has been shown to have the hardness and desirable characteristics discussed herein. (SANTOPRENE is a trademark of Monsanto Company Corporation, 800 N. Lindberg Blvd., St. Louis, Mo. 63166, exclusively licensed to Advanced Elastomer Systems, L.P., 388 S. Main Street, Akron, Ohio 44311.)

[0045] The number of traction segments can be varied, but it has been demonstrated that the optimal number of segments is eight. Additionally, in the first preferred embodiment the size of the notches separating the segments does not compromise the substantially flat plane created by the segments collectively. Were they to do so, they might produce, instead, a surface topography that penetrates green surfaces, as is characteristic of all of the known prior art. This is the common problem of known spike designs.

[0046] In contrast with existing art, the traction and gripping characteristics of the present invention are provided not by projections or extensions depending downwardly from a planar or, more typically, convex, flange. Rather, the traction and gripping characteristics are provided primarily by the substantially circular outer circumference 26 of the planar base member and the outer surfaces 28 of the individual traction segments, which together form a substantially cylindrically-shaped spike, and all of which cooperate functionally to produce traction in every direction and on every circumferential surface of the spike.

[0047] When a number of the golf spikes of the present invention are installed into the sockets or receptacles of a typical golf shoe, the spikes collectively form an array of flat surfaces extending downwardly from the sole of the shoe. Because there are no projections on the spikes, the spikes wear more evenly and more slowly than designs with projections. The flat surface, soft material of the spike, and the readily deformable traction segments also increase wearing comfort due to the shock absorbing characteristics of the material and design, to the fact that weight is broadly distributed over the plurality of planar surfaces on the bottom of the shoe (rather than a plurality of pointed surfaces), and ultimately to the fact that the spike does not affect walking mechanics. Because the spike is flat and soft and will not slide as the foot comes down heel first and at an angle, it does not force the golfer to avoid the appropriate ankle roll and foot pronation associated with each step. The golfer maintains normal walking mechanics and therefore does not expose himself or herself to injuries caused by a suddenly altered, unnatural gait. The soft material actually provides a gentle propulsive effect to assist in walking on hard surfaces. No other known design with effective traction characteristics also provides the wearing comfort and walking advantages of the present invention.

[0048] Further, spikes with projections defining an interior space with the spike's body member tend to accumulate dirt and debris when worn on turf. The pockets or chambers formed by the projections effectively catch and hold dirt and debris on the body of the cleat. By contrast, the flat outer surface and nominal notches forming the traction members of the present invention resist the accumulation of mud and debris, thereby reducing the inherent danger of slipping. This same feature also resists the collection and transplantation and implantation of plant material that might generate or propagate undesirable species of grass onto putting surfaces.

[0049] Moreover, because the spike of the present invention does not have any sharp projections or extensions, body weight is more evenly distributed across the foot when walking and swinging a golf club. As noted this provides multiple benefits, not the least of which is increased traction. Just as importantly, however, the spike's tendency to penetrate and damage putting surfaces is substantially reduced and, in most settings, virtually eliminated. Accordingly, the spike meets the fundamental objectives of both the wearer and golf course greens keepers.

[0050] A second preferred embodiment 30 of the present invention is illustrated in FIGS. 5-8. FIG. 5 is a side perspective view of the second preferred embodiment shown not installed in a shoe. FIG. 6 is a cross-sectional side perspective view in elevation of the spike of FIG. 5 showing the spike's cupping characteristics when installed in a shoe. FIG. 7 is a side view in elevation of the spike of FIGS. 5 and 6 shown not installed in a shoe. FIG. 8 is a cross-sectional side view in elevation of the spike of FIGS. 1-4 and FIGS. 5-7, again showing the spike's cupping characteristics when installed. As will be readily appreciated, FIG. 8 is also illustrative of the behavior of the first preferred embodiment when combined with certain features of the second preferred embodiment.

[0051] As with the first preferred embodiment, the second preferred embodiment comprises a one-piece primary body member 32 having a distal (ground-facing) outer planar surface or face 34 and a proximal sole-facing surface 36, and a substantially circular outer circumference 38.

[0052] The integral self-threading stud 40 is axially disposed from the sole-facing surface of the body member and has a proximal end 40 a and a distal end 40 b. Preferably the stud tapers very slightly from its proximal to its distal end and includes vertical ribbing 42 to reinforce the stud when inserted into a threaded spike socket or receptacle.

[0053] The planar outer surface 34 includes a substantially rectangular aperture, or slot 44, for inserting or removing the spike with a tool.

[0054] FIGS. 5-8 collectively illustrate a novel feature of the inventive spike. The stud 40 of either the first or the second preferred embodiment is preferably manufactured with a length 46 slightly shorter than the depth 48 of the threaded spike socket 50 in the sole S of a shoe into which it is inserted at installation. When tightly screwed into the spike socket, by virtue of the spike's soft composition, the stud may be screwed further into the socket than the length of the stud alone would permit. Thus, the elastic material in the body of the spike, and more particularly the outer planar surface 34, may be pulled slightly downwardly into the socket when the stud is tightly screwed in, inducing a kind of puckering or cupping effect on the outer planar surface (FIGS. 6 and 8). This cupping effect creates a soft rim 36 at the outer circumference of the outer planar surface that increases the traction and gripping effect of the spike on soft surfaces and also enhances its shock absorption and propulsive characteristics on hard surfaces. These views show that in the second preferred embodiment the inventive spike may not include traction segments or digits of any kind. In fact, its gripping characteristics derive solely from the cupped rim formed by a tight installation. Thus the outer planar surface 34 may be entirely flat when not installed, having no projections or surface topography whatsoever.

[0055] In a third preferred embodiment, the shortened stud of the second preferred embodiment and the geometry of the first preferred embodiment are combined to provide a spike with both cupping characteristics discussed supra and the traction digits illustrated in FIGS. 1-4. FIG. 8 shows how this spike cups when installed. Thus, as with the flat outer planar surface of the second preferred embodiment, the traction digits or segments (reference number 14 of FIGS. 1, 3-4) also pucker or cup to form an outer rim 36 at the edge of each of the traction segments. Accordingly, the advantages and most desirable characteristics of both embodiments are obtained in this third embodiment.

[0056] While this invention has been described in connection with preferred embodiments thereof, it is obvious that modifications and changes therein may be made by those skilled in the art to which it pertains without departing from the spirit and scope of the invention. For example, though the disclosed spike is generally adapted for use as a golf shoe spike, there is nothing limiting its use in other athletic or work shoes. Furthermore, the outer periphery of the spike could depart from the substantially circular or cylindrical shape disclosed. In such an instance, the traction segments would be designed with outer edges adjacent to and coincident with the outer edge of the planar base member. Moreover, the material used in fabricating the spike may be tailored to the intended use for the spike, though the thermoplastic rubbers or plastics which remain soft enough to permit cupping is preferable.

[0057] Accordingly, the scope of this invention is to be limited only by the appended claims. 

What is claimed as invention is:
 1. A golf shoe spike for insertion into a threaded spike socket in the sole of a golf shoe, comprising: a primary body member having a ground-facing outer planar surface and a sole-facing surface, said outer planar surface having an outer circumference; a stud axially disposed from said sole-facing surface of said primary body and having a proximal end and a distal end, said stud having a length shorter than the depth of the spike socket into which it is inserted; characterized in that when said spike is inserted and tightened in the threaded spike socket said ground-facing outer planar surface cups to form a raised rim at said outer circumference of said outer planar surface.
 2. The golf shoe spike of claim 1 , wherein said spike is fabricated from a thermoplastic rubber having a Shore A hardness of between 80 and
 94. 3. The golf shoe spike of claim 1 , where said spike is fabricated from a thermoplastic rubber having a Shore A hardness of between 87 and
 90. 4. The golf shoe spike of claim 1 , wherein the primary body member has a substantially circular outer circumference.
 5. The golf shoe spike of claim 1 , wherein said stud is self-threading and tapers from its proximal to its distal end.
 6. The golf shoe spike of claim 5 , wherein said stud includes vertical ribbing.
 7. The golf shoe spike of claim 1 , further comprising a substantially rectangular aperture in said outer planar surface for use in inserting or removing said spike with a tool.
 8. A removable golf shoe spike for insertion into a threaded spike socket, comprising: a planar base member having a sole-facing surface and a ground-facing surface, and a geometric center; a plurality of equidistantly-spaced traction segments integrally formed on said ground-facing surface of said planar base member, said segments extending radially outwardly from said geometric center; a planar outer surface formed by said plurality of traction segments; and a stud integrally formed with and axially disposed from said sole-facing surface of said planar base member, said stud having a proximal end and a distal end and is adapted for screwing into a threaded golf shoe spike socket.
 9. The golf shoe spike of claim 8 wherein said planar base member has a substantially circular outer circumference.
 10. The golf shoe spike of claim 8 wherein said plurality of traction segments are separated by substantially triangular notches in said primary body.
 11. The golf shoe spike of claim 8 wherein said planar base member and said plurality of traction segments collectively comprise a substantially cylindrical shape.
 12. The golf shoe spike of claim 8 wherein said planar outer surface includes a substantially rectangular aperture adapted for engagement with a coin or conventional screwdriver for installation into, and removal of said spike from, a threaded golf shoe female spike socket.
 13. The golf shoe spike of claim 8 where said planar outer surface includes at least two circular openings for engagement with a conventional golf shoes spike wrench.
 14. The golf shoe spike of claim 8 wherein said stud is self-threading and includes a plurality of vertical ribs.
 15. The golf shoe spike of claim 14 where said self-threading stud tapers from its proximal to its distal end.
 16. The golf shoe spike of claim 8 , wherein said stud has a length shorter than the depth of the spike socket into which it is inserted.
 17. The golf shoe spike of claim 16 wherein said spike is fabricated from a thermoplastic rubber, wherein when said spike is tightened in the threaded spike socket said ground-facing outer planar surface cups to form a raised rim at said outer circumference of said outer planar surface.
 18. The golf shoe spike of claim 16 wherein said spike has a shore A hardness of between 80-94.
 19. The golf shoe spike of claim 16 wherein said spike has a shore A hardness of between 87-90. 